A normal shaped charge will punch a long, narrow hole; a cluster charge will shift a much larger volume of material using an array of several charge detonated simultaneously. This technique will blast out an impressive forty to sixty times as much rock or concrete for the same weight of explosive

Clustered explosives and replicating deep digging along with an exoskeleton with portable backhoe arms would enable a soldier to rapidly dig themselves to 150 feet of depth and have an air supply and be able to dig out later when it is safe.
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